Thanks for this reply.
If the advice was given over the phone and there was no covering letter with the CPV application, referring to the specific telephone advice, that is not wonderful but it is not necessarily fatal. If the visa has not yet been refused formally then there might be some scope to argue.
Please question your Mum in more detail. If the visa has been refused, DIAC send a formal letter confirming that it has been refused and there is also a separate sheet of paper headed "Reasons for Refusal" or something similar. The reasons for refusal are usually unintelligible because they refer to obscure sections of the Migration Act that most people have never even heard of, let alone read! For those, one needs someone like Nigel Dobbie who has actually read and understood every word of the relevant legislation.
A formal refusal letter would also mutter about the possibility of an apeal to the MRT. They usually put a paragraph that is little more than a PS about the MRT but it gives the link to the MRT website, I believe.
DIAC occasionally refuse a visa outright with no prior warning but much more frequently they write and tell the applicant that they think they will have to refuse the visa and they give the applicant 28 days in which to offer the applicant's comments about the intended refusal. If your Parents' application has only got as far as this warning stage then it would be worth contacting the Manager of the PVC (don't worry - I have all his direct contact details and will gladly pass those on privately) just to see whether we can rescue the application.
By convention, the names of individual DIAC staff and their contact details are not bandied around publicly on the internet forums because that would not be fair on the individual staff members in most situations. (Occasionally they deserve it, in which case I do not spare them, but mostly they don't deserve any publicity!)
If the visa has actually been refused formally, the probability is that DIAC would not agree to vacate their own refusal. I have known situations where someone has been able to wheedle them into vacating their own refusal but the legislation doesn't actually contain the legal machinery to allow them to do it. The legislation assumes that the Minister will never make a legal mistake and that he will never call the shot wrongly where a Manager has to make a value-judgement about something. Which is a very big ask but Parliaments always imagine that their fellow-pollies are infaiiible! The Minister for Immigration is only an elected politician, after all, and the Immigration Portfolio annoys every single voter in Australia for one reason or another, so the pollie who gets the job of being the Minister for Immi has drawn one of the shorter straws in the box!
Also, if the Minister makes a mistake (or his delegates do) Parliament comfort themselves with the thought that the visa applicant can always Appeal to one of the Tribunals or s/he can apply to the Court for Judicial Review of the decision. It is nice being a politician, I reckon - the real world need never impinge on one's dreamy imaginings and as for hassle and cost, that's what other people are supposed to enjoy putting up with, isn't it?
Also, if a visa has been formally refused and then the refusal is vacated in-house, the relevant Manager runs the risk that DIAC's internal Auditors will start asking questions. Two years later, when nobody can still remember what actually happened or why. So I can understand the Managers' reluctance to overturn formal visa refusals.
So - if the visa has not been formally refused, I think there is definitely enough meat on the bone to make it worth arguing with the Nanager of the PVC. After all, the worst he can do is to refuse the visa formally and he is going to do that anyway unless one puts up a fight, so I would consider it worth having a go at him.
That said, if the visa has been refused formally then it is probable that no amount of trying to bicker with the Manager of the PVC would alter the position. In that situation, I think the decision would be whether or not to launch an Appeal to the MRT.
Based solely on my entirely informal discussions with Tony Coates about Child 3, I don't think it looks brilliant. I suspect that when Child 3 holds a sc 457 Temporary Visa, there would probably need to be some convincing evidence that Child 3 has actually applied for PR - which does not seem to have been the case.
However, I will send you a Private Message with my e-mail address. I am in touch with both Tony Coates and Nigel Dobbie, so between us we would be able to scrounge from free initial advice out of one or both of them. E-mail is the easiest medium at this stage since neither Nigel or Tony are members of Poms in Adelaide.
I think it is important to reassure your Parents that all is not necessarily lost at this stage. They should be aware that it does not look brilliant but it might not be totally hopeless. Long stay tourist visas can now be obtained on-line so that could be done within an hour or two, ergo there is no hurry to make any decisions about that and it would not be wise to do it prematurely. Karen Thorpe has hinted that there might be better ways to do this and she is right.
Please just ask Mum to stay calm, do nothing and just answer a few more questions for the time being.